Cannula for withdrawing a test sample from a test tube



FIG. 1 is a top, left side perspective view of a cannula for withdrawing a test sample from a test tube, showing my new design, the cannula being generally symmetrical about its axis; and

FIG. 2 is a rear, bottom left side perspective view thereof. 

The ornamental design for a cannula for withdrawing a test sample from a test tube, as shown and described. 